title: Relationships between β-amyloid and functional connectivity in different components of the default mode network in aging.
abstract: Although beta-amyloid (Aβ) deposition is a characteristic feature of Alzheimer's disease (AD), this pathology is commonly found in elderly normal controls (NC). The pattern of Aβ deposition as detected with Pittsburgh compound-B positron emission tomography (PIB-PET) imaging shows substantial spatial overlap with the default mode network (DMN), a group of brain regions that typically deactivates during externally driven cognitive tasks. In this study, we show that DMN functional connectivity (FC) during rest is altered with increasing levels of PIB uptake in NC. Specifically, FC decreases were identified in regions implicated in episodic memory (EM) processing (posteromedial cortex, ventral medial prefrontal cortex, and angular gyrus), whereas connectivity increases were detected in dorsal and anterior medial prefrontal and lateral temporal cortices. This pattern of decreases is consistent with previous studies that suggest heightened vulnerability of EM-related brain regions in AD, whereas the observed increases in FC may reflect a compensatory response.
authors.affiliation: Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720, USA. bmormino@berkeley.edu
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: Mormino
authors.forename: Andre
authors.initials: A
authors.lastname: Smiljic
authors.forename: Amynta O
authors.initials: AO
authors.lastname: Hayenga
authors.forename: Susan H
authors.initials: SH
authors.lastname: Onami
authors.forename: Michael D
authors.initials: MD
authors.lastname: Greicius
authors.forename: Gil D
authors.initials: GD
authors.lastname: Rabinovici
authors.forename: Mustafa
authors.initials: M
authors.lastname: Janabi
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Baker
authors.forename: Irene V
authors.initials: IV
authors.lastname: Yen
authors.forename: Cindee M
authors.initials: CM
authors.lastname: Madison
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Miller
authors.forename: William J
authors.initials: WJ
authors.lastname: Jagust
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology / Q000502:physiology*; D016229:Amyloid beta-Peptides / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000473:pathology / Q000502:physiology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D061212:Memory, Episodic; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology*; D049268:Positron-Emission Tomography / Q000379:methods; D055815:Young Adult
chemical_list: D016229:Amyloid beta-Peptides